CPT 99458: RPM Treatment Management — Additional 20 Minutes.
CPT 99458 covers each additional 20 minutes of clinical staff time spent on remote physiologic monitoring treatment management beyond the initial 20 minutes billed under 99457. It is an add-on code that cannot be billed independently — 99457 must be billed as the base code in the same calendar month. The same interactive communication and clinical management requirements apply: staff must review data, make clinical decisions, and communicate with the patient.
Quick Answer
What is CPT 99458?
CPT 99458 is the add-on Medicare billing code for additional RPM treatment management time, covering each additional 20 minutes beyond the initial 99457. It reimburses $41.42 per unit under the 2026 CMS fee schedule (RVU 1.24) and cannot be billed independently — 99457 must serve as the base code. Up to two units can be billed per month, covering up to 60 total minutes of clinical management. Documentation must show cumulative time exceeding the 20-minute base threshold with continued interactive patient communication.
Documentation
Documentation requirements.
Cumulative time log showing total minutes exceeding the initial 20-minute threshold of 99457
Itemized activities performed during the additional time period with dates
Clinical justification for extended monitoring management beyond 20 minutes
Continued interactive communication documentation with patient or caregiver
Reference to base 99457 claim for the same calendar month
Scenarios
Common billing scenarios.
45 minutes total RPM management in a month
BillableClinical staff spends 45 minutes total on RPM treatment management, including data review and three patient calls. Bill 99457 for the first 20 minutes and one unit of 99458 for the additional 25 minutes (which exceeds the 20-minute add-on threshold).
Billing 99458 without 99457
Not BillableA practice bills 99458 for 20 minutes of RPM management but does not have a corresponding 99457 base claim. The claim will be denied because 99458 is an add-on code that requires 99457 as the base.
65 minutes total — two units of 99458
BillableA complex patient with multiple monitored parameters requires 65 minutes of treatment management time. Bill 99457 for the first 20 minutes and two units of 99458 for the additional 45 minutes (two add-on increments of 20+ minutes each).
Only 35 minutes total management time
Not BillableClinical staff logs 35 minutes total of RPM management. Bill 99457 for the first 20 minutes. The remaining 15 minutes does not meet the additional 20-minute threshold for 99458, so only 99457 can be billed.
FAQ
Common questions about CPT 99458.
What is CPT 99458?
CPT 99458 is the add-on Medicare billing code for additional RPM treatment management time beyond the first 20 minutes covered by 99457. Each unit of 99458 covers an additional 20 minutes of clinical staff time spent reviewing monitoring data and communicating with the patient. It reimburses $41.42 per unit under the 2026 CMS fee schedule.
How much does CPT 99458 reimburse in 2026?
CPT 99458 reimburses $41.42 per unit per month under the 2026 CMS national non-facility rate, based on an RVU of 1.24. When added to the base 99457 ($51.77) and device supply 99454 ($52.11), a single add-on brings the monthly RPM total to approximately $145 per patient.
Can 99458 be billed without 99457?
No. CPT 99458 is an add-on code that can only be billed when 99457 is also billed for the same patient in the same calendar month. Submitting 99458 without a corresponding 99457 claim will result in denial. The billing practitioner must be the same for both codes.
How many units of 99458 can be billed per month?
CMS allows up to two units of 99458 per patient per calendar month, covering up to 40 additional minutes beyond the base 99457. Combined with 99457, this allows billing for up to 60 minutes of RPM treatment management. Documentation must support the medical necessity for extended management time.
Can 99458 be billed with 99470 instead of 99457?
No. CPT 99458 can only be billed as an add-on to 99457, not to 99470. The 10-minute management code 99470 (new for 2026) does not support add-on increments. If a patient requires more than 19 minutes of treatment management, bill 99457 (and optionally 99458) instead of 99470.
Related Codes
Other CPT codes.
CCM Initial 20 Minutes
$62.00 • Once per calendar month
RPM Device Supply (16+ Days)
$52.11 • Monthly (per 30-day period)
RPM Clinical Review (First 20 Min)
$51.77 • Once per calendar month
RPM Initial Setup (One-Time)
$21.71 • One-time per episode of care
Complex CCM Initial 30 Minutes
$86.00 • Once per calendar month
PCM Physician Base (30 Min)
$88.00 • Once per calendar month
BHI Care Management (20 Min)
$53.00 • Once per calendar month